The true meaning of "W"

[john1944]

Originally Posted By: Volvo_ST1
Originally Posted By: eljefino
If you want to know first hand what the SAE says about something, you have to pay. A lot.

You won't find it online for free.





I don't need to hear it straight from the horse's mouth. Free, secondhand info is fine.

I find it hard to believe that it's a big secret that "W" stands for wabbit. On the other hand, it's possible that those people who do know really don't want to share their knowledge (for free or at all). That in turn makes me question all sorts of info that is liberally dispensed.


weally?

 

[Doug Hillary]

Hi,
Volvo_ST1 - I've made a brief search of documents from a variety of sources I have going back to the 1930s

In a 1968 support document to SAE J300 "SAE recommended practice" the word "Winter" is mentioned. This is done alongside a reference to lubricants with the "W" nomenclature being measured (ATSM D2602) at 0F and those without the "W" being those measured (ATSM D445) at 210F

In the transition to J300 the initial SAE systems commenced in 1911, were revised in 1923 and "finalised" in 1926 using different measuring criteria and continues the 210F measuring point. This remained in place until 1950 and contained seven viscosity "steps" - SAE 10 to 70!

In 1923 0F measurements were proposed (primitive measuring technologies had previously delayed this measurement point) and the "W" nomenclature was proposed as 10W & 20W "tentative oil classifications for trial use"! A reliable measurement of viscosity at "winter" - low temperatures (at 0F) was the driver!

In 1942 the SAE used 10W and 20W viscosities for the first time. It's my belief that they then stayed in the system as "winter" rated lubricants as lubricant technologies improved and 10W-30 hit the market place around 1952-3 or thereabouts. This called for a dual viscosity measurement

So I have always thought of the "W" as meaning winter - it appears that this is the case. I hope this is of interest

 

[doitmyself]

Adding to Doug's findings, and in agreement with Carboncrew, I'm going to go with the idea that SAE does not formally define W.

"W" is not an abbreviation. Instead, it is a "designation" of one of their oil viscosity classification standards (yea, I know, semantics). The only two terms that I could find that W designates is Winter Grade and/or Low Temperature Viscosity (non SAE references). They could have used any letter to designate the low temperature grade classification standard.

This SAE paper only mentions W grade and non-W grade in reference to standard J 300. No mention of winter: http://www.infineum.com/Documents/Crankc...icants-2010.pdf

By the way, Googling J300 standard comes up with some great reading!

Here's a layman's explanation of J300 and W: http://www.ideas4ag-ed.com/uploads/3/7/0...l_viscosity.pdf

 

[Volvo_ST1]

Originally Posted By: Doug Hillary
Hi,
Volvo_ST1 - I've made a brief search of documents from a variety of sources I have going back to the 1930s

In a 1968 support document to SAE J300 "SAE recommended practice" the word "Winter" is mentioned. This is done alongside a reference to lubricants with the "W" nomenclature being measured (ATSM D2602) at 0F and those without the "W" being those measured (ATSM D445) at 210F

In the transition to J300 the initial SAE systems commenced in 1911, were revised in 1923 and "finalised" in 1926 using different measuring criteria and continues the 210F measuring point. This remained in place until 1950 and contained seven viscosity "steps" - SAE 10 to 70!

In 1923 0F measurements were proposed (primitive measuring technologies had previously delayed this measurement point) and the "W" nomenclature was proposed as 10W & 20W "tentative oil classifications for trial use"! A reliable measurement of viscosity at "winter" - low temperatures (at 0F) was the driver!

In 1942 the SAE used 10W and 20W viscosities for the first time. It's my belief that they then stayed in the system as "winter" rated lubricants as lubricant technologies improved and 10W-30 hit the market place around 1952-3 or thereabouts. This called for a dual viscosity measurement

So I have always thought of the "W" as meaning winter - it appears that this is the case. I hope this is of interest


Hi Doug! Thanks for taking the time.

What I read, and I don't remember the source, was that back in the dark ages the SAE differentiated between single viscosity summer oil and winter oil viscosities. The "W" designated an oil suitable for cold weather use. With multi-grade oil, the "W" simply became the designator for low temperature viscosity, while the second figure stood for the high temperature viscosity.

As for the guy who came up with the designation "W," I think it's safe to presume he was indeed thinking of winter and not just pulling a random letter out of his hat. Or we could ask the Magic Eight Ball.

 

[ARB1977]

I don't know why they have W to begin with. Why not make it a slash or something.

 

[MaDMaXX]

Originally Posted By: ARB1977
I don't know why they have W to begin with. Why not make it a slash or something.


Theny ou should go read/watch why we have multigrade oils these days

It's actually quite interesting. As for why the W is used, it's explained two posts up very well. Like i said though, the development of multigrade oil is the important part.

 

[Volvo_ST1]

Originally Posted By: ARB1977
I don't know why they have W to begin with. Why not make it a slash or something.


Your question has already been answered.

There's already a dash, for example, 10W-30.

Why do you think there are, for example, 20W-20 and 20W-50W oils? Do you believe the "W" has no meaning?

 

[XS650]

Originally Posted By: Volvo_ST1
In this recent thread it is stated that the "W" in the engine oil grade designation, according to the SAE, does not stand for "winter" as commonly claimed by engine oil manufacturers.

Surely, the "W" does have a specific meaning, because a 0W and a 0 oil are not the same. For example, there are 20W-20 and 0W-0 oils.

Does anybody know for what the "W" really stands?


In 1952 SAE added the W spec to SAE J300. Unlike in the present version SAE J300, the W spec was evaluated at 0F with a simple viscosity test for all W grades.

Multiple sources in the intertubes (so it definitely might be true) agree that W original stood for Winter in the 1952 version of J300. Now W stands for W.

W standing for winter reconciles with my memory of oil in the 1960s.

 

[Merkava_4]

Quote:
4. Multi-viscosity

Multi viscosity oils work like this: Polymers are added to a light base (5W, 10W, 20W), which prevent the oil from thinning as much as it warms up. At cold temperatures the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.

Oil Facts

 

[Volvo_ST1]

Originally Posted By: XS650
In 1952 SAE added the W spec to SAE J300. Unlike in the present version SAE J300, the W spec was evaluated at 0F with a simple viscosity test for all W grades.

Multiple sources in the intertubes (so it definitely might be true) agree that W original stood for Winter in the 1952 version of J300. Now W stands for W.

W standing for winter reconciles with my memory of oil in the 1960s.


Thanks, XS650.

 

[Volvo_ST1]

Originally Posted By: Merkava_4
Quote:
4. Multi-viscosity

Multi viscosity oils[snip].

Oil Facts


May I ask what this has to do with my original question?

 

[Shannow]

Doug and XS650...thanks for the posts

 

[Jim Allen]

So...

"Zewo-wabbit-thewty?"

 

[river_rat]

Originally Posted By: Volvo_ST1
Does anybody know for what the "W" really stands?

IIRC, it does not stand for any word. It is just a letter designation based on an old API list of lettered oil characteristics. In other words, it means nothing.
(Now, of course, by common usage it could probably be considered correct to say it stands for winter--but not originally.)

 

[Volvo_ST1]

Originally Posted By: river_rat
Originally Posted By: Volvo_ST1
Does anybody know for what the "W" really stands?

IIRC, it does not stand for any word. It is just a letter designation based on an old API list of lettered oil characteristics. In other words, it means nothing.
(Now, of course, by common usage it could probably be considered correct to say it stands for winter--but not originally.)


The question is, do you remember correctly?

 

[river_rat]

Originally Posted By: Volvo_ST1
The question is, do you remember correctly?

Nope

 

[Shannow]

Came across this today, and found it strangely ironic.

Quote:
After the war, Rohm and Haas introduced PMA VIIs to general industrial and automotive applications. Early passenger car engine oil VIIs were first introduced to the market in 1946. The adoption of “all season” oils in the commercial market was greatly influenced by two events.
First, the automotive manufacturers’ viscosity specification introduction of the new designation “W” (for winter grades); and then by Van Horne’s publication [4] pointing to the possibility of making and marketing cross-graded oils such as the now well-known “10W-30” as well as other cross-grades. By the early 1950s, use of multigrade passenger car oils became widespread in the consumer market. Methacrylates played a major role in enabling the formulation of that era’s multigrade engine oils. The use of PMA VIIs has since been extended to gear oils, transmission fluids, and a broad array of industrial and mobile hydraulic fluids in addition to the early usage in aircraft hydraulic fluids.


vaseghi.org/file/book/shourangiz.pdf

Interesting find, regardless, section of a pretty good book.

Figure 10.14 is cool

 

[Volvo_ST1]

Originally Posted By: Shannow
Came across this today, and found it strangely ironic.

Quote:
After the war, Rohm and Haas
[snip]


Not Röhm and Haas of Plexiglas fame!

 

[TFB1]

Originally Posted By: Volvo_ST1

Surely, the "W" does have a specific meaning, because a 0W and a 0 oil are not the same. For example, there are 20W-20 and 0W-0 oils.

Does anybody know for what the "W" really stands?


Well the popular belief that "W" was for winter has been around for decades, I remember my dad telling me it stood for winter and that was in the late 50s... We had a '55 Chevy that he only used Gulfpride oil, 20W-20 in winter and 30 in the summer...

 

[Bruce T]

It's fine with me if people claim that "W" was never an official abbreviation for a word, so they simply call it the "W grade." It's widely accepted that "W" stands for "Winter" and not "Weight," which is also fine. Even more confusing, 5W-30 at very low temps can refer to both a 5 Winter grade and 5 weight oil.

The important thing is that "W" refers to measurements of extreme low-temperature pumping/cranking by the standards of SAE J300, and it's not confused with the second number for high temp viscosity at 100°C (212°F). Cranking temps can range from -10°C for 25W down to -35°C for 0W. See the third table below:

http://www.tribology-abc.com/abc/viscosity.htm

As Caterham has said, I wish we were provided with intermediate readings at the common temp of 0°C (32°F). It would tell us more about the base oils before any PPD kicked in. Ha, that's probably one reason they don't provide us with any data at 0°C. Of course, the bigger reason would be it's not a standard test yet. I wish it were.